Question
In a school, class ‘M’ has girls equal to 80% of the
boys. Class ‘N’ has 25% less boys than class ‘M’ and 20% more students overall. Find the ratio of number of girls in class ‘M’ to the number of girls in class ‘N’.Solution
ATQ,
Let the number of boys in class ‘M’ = 100x
Then, number of girls in class ‘M’ = 0.80 × 100x = 80x
Number of boys in class ‘N’ = 0.75 × 100x = 75x
Total number of students in class ‘N’ = (100x + 80x) × (120/100) = 216x
Number of girls in class ‘N’ = 216x – 75x = 141x
Required ratio = (80x):(141x) = 80:141
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